Therapeutic fluid flow control apparatus

ABSTRACT

A device which automatically both agitates an anticoagulant medium with inflowing blood during a blood collection process and terminates the process after a predetermined quantity of blood has been collected. The device includes a weight longitudinally slidable on a lever type scale arm to permit accurate selection of the blood quantity collected.

United States Patent 889,217 6/1908 Finch 177/250 1,495,724 5/1924 Blake177/53 1,904,446 4/1933 Gumprich 177/250 2,757,375 7/1956 Rieutord eta1. 259/56 2,784,932 3/1957 Poitras 177/1 2,798,687 7/1957 Hamilton.177/74 2,845,929 8/1958 Strumia 128/276 2,982,286 5/1961 Welch 128/2763,115,152 12/1963 Goldberg et a1. 137/408 Primary ExaminerDalton L.Truluck Att0rneyJohn E. Toupal ABSTRACT: A device which automaticallyboth agitates an anticoagulant medium with inflowing blood during ablood collection process and terminates the process after apredetermined quantity of blood has been collected. The device includesa weight longitudinally slidable on a lever type scale arm to permitaccurate selection of the blood quantity collected.

I e7 a9 PATENTEDJANPBIQYI 3557.789

SHEET 3 BF 3 Izwezziaai- Edzvwd JPaii'Jm,

1 THERAPEUTIC FLUID FLOW CONTROL APPARATUS This invention relatesgenerally to a therapeutic fluid flow control apparatus and, morespecifically relates to an apparatus forthe collection of blood.

There exist various therapeutic applications wherein a precise controlof fluid flow is required. Generally the applications entail thetransfer of predetermined specific quantities of fluid from one locationto another. Typical examples include the transfer of blood from a blooddonor to a suitable collection vesseland the transfer of blood, bloodpreparations, and other therapeutic fluids from suitable containers to apatient. Since the permissible fluid flow rates are low, a relativelylengthy period generally is required for transfer of a desired fluidquantity. Thus, a system which accurately and automatically controls theamount of fluid transferred is extremely useful both for reasons ofexactness and for eliminating the requirement for continuous monitoringof the transfer process by highly trained personnel.

U.S. Pat. No. 2,784,932 describes such a system including a stationarymember which pivotally supports a two-arm scale lever having one armadapted to support the blood collection vessel and an opposite armsupporting a weight selected to counterbalance the combined weight ofthe collection vessel and desired quantity of blood. After transfer ofthe predetermined weight of blood into the collection vessel, theposition of the lever automatically shifts to pinch closed the flexibletubing joining the collection vessel and blood donor thereby terminatingthe collection process.

Although the device described in the above noted patent substantiallysimplified blood collection techniques, a need exists for improvedequipment of this type, particularlyfor a unit offering greater andsimpler selectivity of the fluid quantities controlled. However, fluidquantity adjustments should not be easily susceptible to modification byunauthorized personnel. Also, although automatically stopping thecollection process after accumulation of a desired quantity of blood,the described device does not completely eliminate the requirement forsupervision in that trained personnel must periodically agitate thecollection vessel to insure thorough mixing of the previously introducedanticoagulant'medium and the inflowing blood. 7

The object of this invention, therefore, is to provide a therapeuticfluid flow control device which automatically stops fluid flow aftertransfer of a given predetermined fluid quantity and which exhibits asimpler and moreselective adjustment mechanism for determining thequantity of fluid controlled. I p

Another object of this invention is to provide a therapeutic fluid flowcontrol device of the above featured type wherein the adjustmentmechanism is relatively tamper-proof from unauthorized personnel.

Another object of this invention is to provide a blood collectioncontrol device which both terminates ablood collection process aftertransfer of a desired quantity of blood and agitates the blood containerduring thetransfer process to insure thorough mixing of a previouslyintroduced anticoagulant medium with the incoming blood.

One feature of this invention is a provision of a therapeutic fluid flowcontrol unit of the type described in the above noted patent andincluding a slidable selectorweight adapted for selective engagementwith a plurality of graduated stops on the unit's counterbalance leverarm The selector weight permits simple and accurate selection of theprecise quantity of transferred fluid which will actuate the lever armand terminate the transfer process.

Another feature of this invention is the provision of a therapeuticfluid flow control device of the above featured type including areleasable biasing mechanism which inhibits relative movement betweenthe selector weight and counterbalance lever arm. The biasing mechanismimproves the stability of the device and prevents unintentional alteringof a preselected fluid quantity setting by inadvertent movement of theselector weight.

Another feature of this invention is the provision of a therapeuticfluid flow control'device of the above featured type wherein thereleasable biasing mechanism is substantially .enclosed by the selectorweight so as to-be substantially hidden from view..This,feature rendersthe device relatively tamper-proof from unauthorized personnelunfamiliar with the device s operation.

Another feature of this invention is the provision of a therapeuticfluid flow control device of the above featured type wherein the releasefor the releasable biasing mechanism is disposed in the bottom surfaceof the selector weight so as to be somewhat concealed from the view ofunauthorized personnel.

Another feature of this invention is the provision of a therapeuticfluid flow control device of the above featured type particularly suitedfor blood collection and including a movable support for the bloodcollecting vessel. An electrically energizable drive means is coupled tothe vessel support and is adapted upon energization to produce movementthereof. Automatically induced movement of the blood collection vesselinsures continuous agitation of the incoming blood with the previouslyintroduced anticoagulant medium thereby eliminating the requirement thatthis necessary action be performed manually.

Another feature of this invention is the provision of a therapeuticfluid flow control device of the above featured type wherein the movableblood collection vessel support includes a cradle attached to a leverarm of the device by a yoke member, and the drive means comprises anelectric motor and drive shaft operatively coupled between the cradleand yoke member and adapted upon energization to produce a rockingmovement of the cradle. This arrangement provides in a relatively simpleand efficient structure the desired continuous mixing of blood andanticoagulant medium.

Another feature of this invention is the provision of a therapeuticfluid flow control device of the above featured type wherein theelectrical leads connected to the electric motor include intermediateportions attached to the stationary part of the device. By fixing theelectrical leads to the units stationary portion, the possibility ofhaving undesired forces exerted by the electrical cord onthe balancedlever arm is eliminated.

These and other objectsand features of the present invention will becomemore apparent upon a perusal of the following specificationtaken inconjunction with the accompanying drawings wherein:

FIG. 1 is a front view'of a preferred embodiment of the invention;

FIG. 2 is a top view of the embodiment shown in FIG. 1-,

FIG. 3 is an end view of the embodiment shown in FIGS. 1 and 2;

FIG. 4 is a cross-sectional view taken along the lines 4-4 of FIG. 1;

FIG. 5 is a front view of the biasing pin 63 shown in FIG. 4; and

FIG. 6 is a partial view showing the embodiment of FIG. 1 in an actuatedposition.

Referring now to FIGS. l3, there is shown the stand 11 supporting thecollapsible, sealed plastic blood pack 12. The

blood pack 12 may be, for example, of the type shown and described inUS. Reissue Pat. No. 25,129. Attached to the blood pack 12and-communicating with the interior thereof is the flexible tubing 13.The opposite end of the flexible tubing 13 terminates with thehypodermic needle 14 suitable for insertion into the vein of a blooddonor (not shown) so as to per mit filling of the blood pack 12 in'theconventional manner.

Included in the stand 11 is the cylindrical rod 15 which extends throughan aperture 16 in the stationary support block 17 and is fixed thereonby the thumbscrew 18. The stationary block 17 includes the rear blockportion 19 and the overhanging front block portion 21 possessing thelateral slot 22.

Extending below the front block portion 21 ahead of the lateral slot 22is the projection 23 having the laterally disposed groove 24 whichaccommodates the flexible tubing 13. The position of the flexible tubing13 is established also by the bracket 25 mounted on the stationary frontblock portion 21. The lower end of the cylindrical rod 15 is supportedwithin the base member 26.

The two-arm lever member 28 is pivotally supported within the slot 22 bythe pivot pin 27 which extends between the rear block portion and theprojection 23. Forming the lever member 28 are the integrally joinedupwardly inclined arm 29 and the horizontal arm 31. The triangularlyshaped nip 32 is formed on the horizontal arm 31 directly adjacent theprojection 23. In the inactivated position shown in FIG. 1, the upperapex of the nip 32 is aligned with the lower edge of the groove 24.

Suspended from the end of the inclined arm 29 is the blood pack supportassembly 35 including the cradle pan 36 and attached yoke member 37. Theknob 38 on the inclined lever arm 29 accommodates an aperture in theflattened end portion 39 of the yoke member 37 which is retained inposition by the clip 41. The bottom of the yoke member 37 is formed bythe horizontal portions 42 joined by the arched portion 43. Attachingthe cradle pan 36 and yoke member 37 are the rings 44 which permitrotational movement of the horizontal yoke portions 42.

Fixed to the bottom surface of the cradle pan 36 is the electric motor45 having the eccentric drive shaft 46. The shaft 46 is received byaligned apertures in the U-shaped disc 47 mounted on the arched yokeportion 43. In response to forces applied by the shaft 46, the disc 47moves both rotationally and longitudinally with respect to the archedportion 43. The electrical motor leads 48 extend through the hollowinterior of the yoke member 37 and are supported by the clip 49 on therear surface of the inclined lever arm 29 and by the terminal box 51mounted on the rear block portion 19. The leads 48 terminate with theplug 52 adapted for insertion into a conventional electrical wall socket(not shown).

Secured to the end of the horizontal lever arm 31 by the recessed screw55 is the counterbalance weight 56. Also mounted on the horizontal arm31 for longitudinal sliding movement thereon is the selector weight 57.As shown in FIG. 4, the selector weight possesses an internal slot 58which accommodates the horizontal lever arm 31 and an adjoining frontalopening 59 which exposes graduations printed on the front face thereof.The selector weight 57 also possesses a vertically disposed cylindricalbore 61 having an opening in the selector weights bottom surface 62.Retained within the cylindrical bore 61 is a releasable biasingmechanism including the cylindrical pin 63 and the compression springmember 64. The cylindrical pin 63 possesses a groove 65 of slightlygreater width than the horizontal lever arm 31 which it accommodates.Formed in the upper edge of the groove 65 are the plurality of uniformlyspaced teeth 66, shown in FIG. 5, adapted for simultaneous engagementwith selected sets of the notches 67 cut in the upper edge of thehorizontal lever arm 31. The uniformly spaced notches 67 are alignedwith the graduations printed on the front surface of the horizontallever arm 31.

To operate the control device 11, the support block 17 is located at adesirable height on the support rod 15 and secured by tightening of thethumbscrew 18. The selector weight 57 is adjusted longitudinally on thehorizontal lever arm 31 until the indicator 69 points to a graduationindicating the weight at which actuation of the scale lever 28 isdesired. Then the motor 45 is energized by inserting the plug 52 into anelectrical outlet (not shown) and the needle 14 is injected into a veinof a blood donor (not shown) to initiate the blood collecting operation.

It will be appreciated that the graduations on the horizontal scale arm31 are calibrated such that the combined moments exerted by the weights56 and 57 will balance exactly the moment produced on the inclined leverarm 29 by the support assembly 25 and a load having a total weight equalto that indicated by the pointer 69. This total weight comprises thepredetermined known weights of the plastic blood pack 12 and theanticoagulant medium previously introduced therein, in addition to theweight of any blood collected in the pack 12. Normally, the operatorwill use a suitable conversion table which indicates the correct totalweight setting necessary for collection of a predetermined quantity ofblood in a given pack 12. Thus, when the desired quantity of blood hasaccumulated in the blood pack 12, the moment produced by the totalweight on the inclined lever arm 29 will overcome that provided by theweights 56 and 57. Accordingly, the scale arm 28 will rotate clockwiseabout the pivot pin 27 into the position shown in FIG. 6. The resultantmovement of the nip 32 with respect to the stationary front blockportion 21 pinches and closes the flexible tubing 13 thereby preventingfurther blood transfer and terminating the collection process.

. As the scale lever 28 moves between the positions shown in FIGS. 1 and6, there is an increase in the length of the moment arm for the forceapplied by the support assembly 35 which length is determined by thehorizontal distance between the pivot pin 27 and the knob 38.Conversely, the lengths of the moment arms for the forces exerted by theweights 56 and 57 as determined by the horizontal distances thereof fromthe pivot pin 27 are decreased. Thus, there is an increase of torque inthe clockwise direction. This increased torque in addition to themechanical advantage provided by the substantially different radii ofaction of the knob 38 and nip 32 from the pivot pin 27 insure positiveclosure of the tubing 13.

Adjustment of the selector weight 57 is easily accomplished by pushingupward on the exposed end 68 of the release pin 63. This forces therelease pin 63 upward and eliminates engagement between the teeth 66 andthe notches 67 and facilitates free longitudinal movement of theselector weight 57 on the horizontal lever arm 31. However, afterattainment of a desired longitudinal position and release of the pin 63the compression spring 64 again urges the teeth 66 into engagement withthe aligned set of notches 67 to inhibit further longitudinal movementof the selector weight 57. The use of a plurality of engaging teeth 66on the pin 63 improves accuracy by enhancing the locational stability ofthe selector weight 57. Furthermore, the concealment of the releasemechanism within the selector weight 57 and location of the actuator pinend 68 in the weights bottom surface 62 reduce the likelihood ofundesired readjustment of the selector weight '57 by unauthorizedpersonnel.

During the collection process, the electrically energized motor 45produces rotation of the eccentric shaft 46. The resultant forcesexerted between the shaft 46 and the mechanically coupled arched portion43 produce a rocking movement of the cradle pan 36 between the positionsshown dotted in FIG. 1. This rocking motion continuously agitates theblood and anticoagulant contents of the blood pack 12 insuring thoroughmixing thereof. Thus, the requirement for manual manipulation of thepack during the collection process is eliminated.

Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. For ex ample, althoughdescribed in connection with the preferred blood collection application,it will be obvious that the control device 11 could be. used for otherpurposes including the transfer of therapeutic fluids from a vessel to apatient. In that case the lever arm 28 would be modified such that theinclined arm 29 retained the weights 56 and 57 and the horizontal arm 31supported a fluid supply vessel. In such an arrangement, the selectedweight would be adjusted so as to produce automatic actuation of thescale lever 28 and termination of the fluid transfer process after apredetermined quantity of fluid had been removed from the supply vessel.Also, drive mechanisms other than an electrical motor could be used toproduce movemeritofthe cradle pan 36. It is, therefore, to be understoodthat within the scope of the appended claims the invention can bepracticed otherwise than as specifically described.

v lclaim:

1. Therapeutic fluid flow control apparatus of the type including astationary support, a two-arm lever movable thereon about a pivot point,one arm of the lever adapted to support a fluid-collecting closedcontainer having a length of flexible tubing for delivering fluidthereto, a counterbalance on the other lever arm, tube holding means forsupporting the flexible tubing in a fixed position with respect to saidstationary support and said lever, and pinch means adapted to pinchclosed the flexible tubing in response to relative movement between saidstationary support and said lever; the improvement to which comprises:

a selector weight supported by and slidable on said other lever arm,said selector weight having top, bottom and side surfaces and defining acentral cavity communicating with an opening in said bottom surface;

a plurality of graduated stops on said other lever arm adapted forselective engagement with said selector weight so as to fix thelongitudinal position thereof on said other lever arm; and

a releasable biasing means for preventing relative movement between saidselector weight and said other lever arm, said releasable biasing meansbeing completely recessed within said selector weight cavity so as to besubstantially hidden from view and manually operable only through saidopening in said bottom surface to permit relative movement between saidselector weight and said other lever arm. I I

2. Therapeutic fluid flow control apparatus according to claim 1 whereinsaid releasable biasing means comprises release means disposed in saidcavity and adapted for manual actuation through said opening todeactivate said biasing means and allow said relative movement betweensaid selector weight and said other lever arm.

3. Therapeutic fluid flow control apparatus according to claim 2 whereinsaid graduated stops comprise longitudinally disposed notches in saidother lever am, said releasable biasing means comprises a pin memberslidably mounted within said cavity in said selector weight, said cavitybeing defined by a bore terminating in said bottom surface of saidselector weight so as to expose an end of said pin member reforming saidrelease means, said pin member having projection means adapted forselective engagement with said notches, and said releasable biasingmeans further comprising a spring member biasing said pin memberdownward and said projection means into engagement with said notches. I

4. Therapeutic fluid flow control apparatus according to claim 3 whereinsaid projection means comprises a plurality of teeth spaced forsimultaneous engagement with said notches in said other lever arm.

5. Blood collection apparatus comprising:

movable support means adapted to hold a blood collecting closedcontainer connected to a blood donor by a flexible tubing, scale meansfor indicating the weight of blood collected in the closed container;

an electrically energizable drive means coupled to said movable supportmeans and adapted upon energization to produce movement thereof andagitation of the fluid content of the closed container;

closure means adapted to automatically interrupt blood flow by closingthe flexible tubing in response to an indication by said scale meansthat a predetermined weight of blood has been collected in the closedcontainer; and

wherein said scale means comprises a two-arm lever pivotally mounted ona stationary support, said movable support means is attached to one armof the lever and is movable with respect thereto, a counterbalance isat- 5 tached to the other lever arm, and said closure means comprisespinch means adapted to pinch closed the flexible tubing in response to apredetermined relative movement between said stationary support and saidlever.

6. Blood collection apparatus according to claim 5 wherein said movablesupport means comprises a cradle attached to said one lever arm by ayoke member adapted to support the closed container, and said drivemeans comprises an electric motor and drive shaft operatively coupledbetween said cradle and said yoke member and adapted upon energizationto produce movement of said cradle so as to agitate the blood content ofthe closed container.

7. Blood collection apparatus according to claim 6 includ- I ingelectrical leads connected to said electric motor, said leadsterminating with a plug adapted for connection to a source of electricalpower and having an intermediate portion attached to said stationarysupport.

8. Blood collection apparatus according to claim 6 including a selectorweight supported by and slidable on said other lever arm, and aplurality of graduated stops on said other lever arm adapted forselective engagement with said selector weight so as to fix thelongitudinal position thereof on said other lever arm.

9. Therapeutic fluid flow control apparatus according to claim 8including a releasable biasing means for inhibiting relative movementbetween said selector weight and said other lever arm.

l0. Therapeutic fluid flow control apparatus according to claim 9wherein said releasable biasing means is substantially enclosed by saidselector weight so as to be substantially hidden from view.

11. Therapeutic fluid flow control apparatus according to claim 10wherein said releasable biasing means comprises release means disposedin the bottom surface of said selector weight and adapted upon actuationto deactivate said biasing means and allow uninhibited relative movementbetween said selector weight and said other lever-arm.

12. Therapeutic fluid flow control apparatus according 6 downward andsaid projection means into engagement with said notches.

13. Blood collection apparatus according to claim 12 including aselector weight supported and slidable on said other lever arm, and aplurality of graduated stops on said other lever arm adapted forselective engagement with said selector weight so as to fix thelongitudinal position thereof on said other lever arm. 1

l4. Therapeutic fluid flow control apparatus according to claim 13wherein said projection means comprises a plurality of teeth spaced forsimultaneous engagement with said notches in said other lever arm.

1. Therapeutic fluid flow control apparatus of the type including astationary support, a two-arm lever movable thereon about a pivot point,one arm of the lever adapted to support a fluid-collecting closedcontainer having a length of flexible tubing for delivering fluidthereto, a counterbalance on the other lever arm, tube holding means forsupporting the flexible tubing in a fixed position with respect to saidstationary support and said lever, and pinch means adapted to pinchclosed the flexible tubing in response to relative movement between saidstationary support and said lever; the improvement to which comprises: aselector weight supported by and slidable on said other lever arm, saidselector weight having top, bottom and side surfaces and defining acentral cavity communicating with an opening in said bottom surface; aplurality of graduated stops on said other lever arm adapted forselective engagement with said selector weight so as to fix thelongitudinal position thereof on said other lever arm; and a releasablebiasing means for preventing relative movement between said selectorweight and said other lever arm, said releasable biasing means beingcompletely recessed within said selector weight cavity so as to besubstantially hidden from view and manually operable only through saidopening in said bottom surface to permit relative movement between saidselector weight and said other lever arm.
 2. Therapeutic fluid flowcontrol apparatus according to claim 1 wherein said releasable biasingmeans comprises release means disposed in said cavity and adapted formanual actuation through said opening to deactivate said biasing meansand allow said relative movement between said selector weight and saidother lever arm.
 3. Therapeutic fluid flow control apparatus accordingto claim 2 wherein said graduated stops comprise longitudinally disposednotches in said other lever arm, said releasable biasing means comprisesa pin member slidably mounted within said cavity in said selectorweight, said cavity being defined by a bore terminating in said bottomsurface of said selector weight so as to expose an end of said pinmember reforming said release means, said pin member having projectionmeans adapted for selective engagement with said notches, and saidreleasable biasing means further comprising a spring member biasing saiDpin member downward and said projection means into engagement with saidnotches.
 4. Therapeutic fluid flow control apparatus according to claim3 wherein said projection means comprises a plurality of teeth spacedfor simultaneous engagement with said notches in said other lever arm.5. Blood collection apparatus comprising: movable support means adaptedto hold a blood collecting closed container connected to a blood donorby a flexible tubing, scale means for indicating the weight of bloodcollected in the closed container; an electrically energizable drivemeans coupled to said movable support means and adapted uponenergization to produce movement thereof and agitation of the fluidcontent of the closed container; closure means adapted to automaticallyinterrupt blood flow by closing the flexible tubing in response to anindication by said scale means that a predetermined weight of blood hasbeen collected in the closed container; and wherein said scale meanscomprises a two-arm lever pivotally mounted on a stationary support,said movable support means is attached to one arm of the lever and ismovable with respect thereto, a counterbalance is attached to the otherlever arm, and said closure means comprises pinch means adapted to pinchclosed the flexible tubing in response to a predetermined relativemovement between said stationary support and said lever.
 6. Bloodcollection apparatus according to claim 5 wherein said movable supportmeans comprises a cradle attached to said one lever arm by a yoke memberadapted to support the closed container, and said drive means comprisesan electric motor and drive shaft operatively coupled between saidcradle and said yoke member and adapted upon energization to producemovement of said cradle so as to agitate the blood content of the closedcontainer.
 7. Blood collection apparatus according to claim 6 includingelectrical leads connected to said electric motor, said leadsterminating with a plug adapted for connection to a source of electricalpower and having an intermediate portion attached to said stationarysupport.
 8. Blood collection apparatus according to claim 6 including aselector weight supported by and slidable on said other lever arm, and aplurality of graduated stops on said other lever arm adapted forselective engagement with said selector weight so as to fix thelongitudinal position thereof on said other lever arm.
 9. Therapeuticfluid flow control apparatus according to claim 8 including a releasablebiasing means for inhibiting relative movement between said selectorweight and said other lever arm.
 10. Therapeutic fluid flow controlapparatus according to claim 9 wherein said releasable biasing means issubstantially enclosed by said selector weight so as to be substantiallyhidden from view.
 11. Therapeutic fluid flow control apparatus accordingto claim 10 wherein said releasable biasing means comprises releasemeans disposed in the bottom surface of said selector weight and adaptedupon actuation to deactivate said biasing means and allow uninhibitedrelative movement between said selector weight and said other lever arm.12. Therapeutic fluid flow control apparatus according to claim 11wherein said graduated stops comprise longitudinally disposed notches insaid other lever arm, said releasable biasing means comprises a pinmember slidably mounted within a bore in said selector weight, saidbores terminating in the bottom surface of said selector weight, saidbores terminating in the bottom surface of said selector weight so as toexpose an end of said pin member forming said release means, said pinmember having projection means adapted for selective engagement withsaid notches, and said releasable biasing means further comprising aspring member biasing said pin member downward and said projection meansinto engagement with said notches.
 13. Blood collection apparatusaccording to claim 12 including a selector weight supported and slidableon said other lever arm, and a plurality of graduated stops on saidother lever arm adapted for selective engagement with said selectorweight so as to fix the longitudinal position thereof on said otherlever arm.
 14. Therapeutic fluid flow control apparatus according toclaim 13 wherein said projection means comprises a plurality of teethspaced for simultaneous engagement with said notches in said other leverarm.